Your boiler is taking a short, programmed break to prevent it from turning on and off too frequently, which protects the system and saves energy.
This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.
Technical description: Anti cycling mode (after heating operation)
What causes this fault?
This status occurs when your boiler has reached its target temperature and needs to wait a few minutes before firing up again. It physically happens to prevent 'short-cycling,' which is when the burner turns on and off too rapidly, causing unnecessary wear and tear. The system is simply waiting for the water in your radiators to cool down slightly so it can run more efficiently.
This code is more frequent in spring and autumn when the weather is milder and your home requires less heat to stay warm.
DIY fix possible
Wait 15 to 20 minutes for the countdown to end automaticallyEnsure all radiator valves are fully open to allow heat to dissipateCheck that the room thermostat is set at a temperature higher than the current room temperature
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